FAA Has Not Resolved Persistent Issues With SkyWest's Maintenance Practices

Date Issued

Monday, July 28, 2025

Submitting OIG

Department of Transportation OIG

Agencies Reviewed/Investigated

Department of Transportation

Components

Federal Aviation Administration

Report Number

AV2025038

Report Description

Our Objective(s)To assess FAA's oversight of SkyWest Airlines' maintenance practices. Specifically, we evaluated FAA's actions to address SkyWest's maintenance noncompliance and violations.
Why This AuditAviation safety is FAA's priority for the 2.9 million passengers that take 45,000 flights a day in the National Airspace System. In prior audits, we found weaknesses in FAA's oversight of maintenance at other airlines. We initiated this audit as part of our ongoing work reviewing FAA's oversight of air carrier maintenance programs.
What We FoundFAA's oversight of SkyWest's maintenance practices does not fully comply with Agency guidance.

FAA's Certificate Management Office (CMO) has not resolved issues with SkyWest's remote return to service maintenance practices for over 4 years.
The CMO also does not always adhere to FAA guidance when addressing SkyWest's noncompliance; CMO leaders are directing inspectors to use a method not included in FAA guidance to achieve compliance.
Delays in the CMO's access to SkyWest's data, CMO leadership and staff turnover, and ineffective communication have also slowed the resolution of SkyWest's noncompliance.
CMO inspectors do not always identify recurring noncompliance; CMO leaders may not be using the most effective tools to address repetitive noncompliance with more comprehensive solutions.
FAA's Safety Assurance System database surveillance documentation options do not fully align with FAA guidance.

RecommendationsWe made 7 recommendations to improve FAA's oversight of SkyWest Airlines' maintenance.

Report Type

Audit

Agency Wide

Yes

Number of Recommendations

Questioned Costs

Funds for Better Use

Report updated under NDAA 5274

External Link

https://www.oig.dot.gov/library-item/46882

Open Recommendations

This report has 7 open recommendations.

Recommendation Number	Significant Recommendation	Recommended Questioned Costs	Recommended Funds for Better Use
5	Yes	$0	$0
Clarify within inspector guidance the proper use of General Correspondence letters to ensure they are not used in place of Compliance Action letters.
6	Yes	$0	$0
Reinforce through inspector training the process for identification of repeat findings and the comprehensive resolution of these findings.
7	Yes	$0	$0
Update guidance and provide training for Principal Inspectors on the proper categorization of actions used to address inspector findings in Safety Assurance System.
2	Yes	$0	$0
Establish clear procedures on how Certificate Management Offices should address significant delays in obtaining air carrier data, including defining an escalation process.
3	Yes	$0	$0
Provide formal guidance to Certificate Management Offices to aid in consistent internal communication and Compliance Action processing during periods of key personnel turnover.
1	Yes	$0	$0
Provide training or formal instruction to managers and inspectors on how to identify and resolve systemic hazards.
4	Yes	$0	$0
Reinforce a structured resolution process within the Compliance Action framework that includes documented escalation procedures, mediation steps, and clear criteria for resolving inspector disagreements to ensure consistency and improve adherence to FAA policy.